This month I have been working on the production lines for building ships. The interface and layout has been finished, but it is not fully functioning yet. However I'm quite happy with how it is looking.

On each production line group in the screenshot it shows:

(Top row)

Priority (higher priorities are first in line for available resources)

Ship being built

Production efficiency level bar

Remove production line button

(Middle row)

Repeat (for building a continuous amount of the ship)

Amount (can manually type the amount in the box or use the plus/minus buttons)

Assign shipyards

Assign maximum number of shipyards

Metals required per ship (red text if there is a shortage)

(Bottom row)

Time remaining to build the current ship

Number of ships stockpiled or in demand

(Right)

Increase/decrease priority buttons

The amount of shipyards assigned to a production line affects the build speed of each ship.

There will be a maximum limit of 20 shipyards you can assign to each production line. This is to prevent ships being built too quickly, but you can create multiple production lines of the same ship.

The total amount of production lines may be limited in some way, for example tied into how many shipyard facilities you have built.

Production Efficiency

Each production line has an efficiency level that is a modifier on the assigned shipyards output. This is shown as a progress bar to the right of the ship name. The efficiency level starts at 10% and slowly increases each day. Assigning more shipyards to the production line will decrease the efficiency level.

Once the specified amount of ships have been built, the production line goes to an idle state. The shipyards will remain assigned to it and unavailable for use elsewhere, unless you reassign them. I haven't decided yet whether the production efficiency level will decrease or not while idle...